车辆与构件类图

Engine

+ speed          : float

+ accelerate (float value) : void+ decelerate (float value) : void

Vehicle

+ serialNumber : String+ manufacturer : String+ version           : String+ engine            : Engine+ brake              : Brake

+ drive (int status)    : void+ maintain ()             : void

Brake

+ status : boolean

+ braking ()     : void+ stopBrake () : void

public class Brake {\tpublic boolean status;\t\tpublic void braking () {\t\tSystem.out.println(\"The car is braking...\");\t\tthis.status = true;\t}\tpublic void stopBrake () {\t\tSystem.out.println(\"Braking is being cancelled...\");\t\tthis.status = false;\t}} 

public class Engine {\tpublic float speed;\t\tpublic void accelerae (float value) {\t\tSystem.out.println(\"The car is accelerating...\");\t\tthis.speed += value;\t\tSystem.out.println(\"The current speed is : \" + speed + \"km/h\");\t}\tpublic void decelerate (float value) {\t\tSystem.out.println(\"The car is slowing...\");\t\tthis.speed += value;\t\tif(this.speed < 0) this.speed = 0;\t\tSystem.out.println(\"The current speed is : \" + speed + \"km/h\");\t}}